- an organism that lives on or in an organism of another species, known as the host, from the body of which it obtains nutriment.
- a person who receives support, advantage, or the like, from another or others without giving any useful or proper return, as one who lives on the hospitality of others: They are greedy politicians, parasites with their snouts in the public trough.
- (in ancient Greece) a person who received free meals in return for amusing or impudent conversation, flattering remarks, etc.
- an animal or plant that lives in or on another (the host) from which it obtains nourishment. The host does not benefit from the association and is often harmed by it
- a person who habitually lives at the expense of others; sponger
- (formerly) a sycophant
